DESCRIPTION (provided by investigator): With the worldwide rise of terrorism and the events of September 11th, there is increased interest in terrorism's psychological impact, and in particular, its relationship to Post Traumatic Stress Disorder (PTSD), depression, and general psychological distress, as well as unhealthy behavior (i.e., chemical use/abuse and smoking). This is a critical U.S. public health issue as planning and preparedness are called for in case of future terrorist events against U.S. targets. To date, studies have not examined the effects of multiple or ongoing terrorism and accordingly how people's resiliency and vulnerability contribute to psychological distress or to unhealthy behavior in response to multiple terrorist threats or strikes. Understanding major multiple traumas'impact is theoretically important as we need to conceptualize how these resiliency and vulnerability factors behave over time and multiple traumatic demands. We will conduct three studies in Israel. In Study I, 1,500 Jewish and Arab (Moslem and Christian) individuals will be surveyed prospectively by phone on three occasions, six months apart. This will allow examination of causal modeling regarding how terrorism impacts individuals over time. In Study 2, we will survey 1,000 individual Jews and Arabs every three-months for 24 months (i.e., n=8,000), with complete replacement (i.e., a new sample each 3 months). This will allow for more mesosocial representation of how terrorism impacts the population in general over time. In studies 1 and 2 we will examine (1) how terrorist events affect PTSD, depression, general psychological distress, and unhealthy behavior (i.e., chemical use/abuse, smoking), (2) whether resiliency factors continue to limit negative trauma sequalae when terrorism and threat of terrorism is ongoing, (3) whether vulnerability factors become increasingly negative in exacerbation of PTSD, depression, general psychological distress, and unhealthy behavior as terrorist events and threats of terrorism continue, and (4) how exposure to terrorism and subsequent PTSD, depression, and general psychological distress are, in turn, related to a defensive coping style, characterized by support for extreme political violence, authoritarianism, and ethnocentrism. In Study 3 we will interview 150 individuals (drawn from Study 2) by telephone and then in-person using standardized clinical interviews (50 Hebrew, 50 Russian, and 50 Arabic). This will enable examination of the validity of phone estimates of diagnosis of PTSD and depression, in particular.